Inhibition of the Vancomycin Resistance in Staphylococcus aureus in Egypt Using Silver Nanoparticles.

Staphylococcus aureus is a major human pathogen that is sometimes resistant to vancomycin. In this study, the prevalence of vancomycin-resistant Staphylococcus aureus (VRSA) was studied. 100 isolates of S. aureus were identified based on biochemical and molecular evidence. The antibiotic susceptibility of the studied isolates was tested against 13 antibiotics by the disc diffusion method that showed 24 vancomycin-resistant isolates. The minimum inhibitory concentrations (MICs) were estimated by the agar dilution method to determine vancomycin intermediate-resistant S. aureus (VISA) and VRSA. The resistance gene cluster (vanA, vanR, vanH, and vanY) was amplified by PCR and then sequenced. Amplification of vanA and vanR genes showed that they are present in 21.4% and 14.3% of VRSA isolates, respectively, whereas none of the studied genes has been detected in VISA strains. A significant antimicrobial effect toward VRSA isolates using silver nanoparticles (AgNPs) synthesized from S. aureus and rosemary leaves was recorded. This study confirmed the existence of VRSA strains in Egypt. Furthermore, the use of silver nanoparticles inhibits these vancomycin-resistant S. aureus strains in vitro.

Exploring the Antifungal Activity and Action of Saussurea costus Root Extracts against Candida albicans and Non-albicans Species.

The isolation and assessment of the active constituents in polar and non-polar crude extracts of Saussurea costus roots as antifungal agents, against Candida albicans and non-C. albicans (NAC) species, was the aim of this current investigation. The SEM "Scanning electron microscopy" imaging provided potential action modes of n-hexane extract (nhhE) toward Candida spp., whereas the TLC-DB "Thin layer chromatography-direct bioautography" was employed for detecting the anticandidal compounds. nhhE had the greatest biocidal activity against all strains and clinical isolates of Candida spp. with maximum zones of inhibition. SEM revealed the occurrence of irregular, dense inclusions of C. albicans cell walls after treatment with nhhE for 12 h. Complete morphological distortions with lysed membranes and deterioration signs appeared in most treated cells of C. parapsilosis. The most effectual compound with anticandidal activity was isolated using TLC-BD and identified as sesquiterpene by GC/MS analysis. The infra-red analysis revealed the presence of lactone ring stretching vibrations at 1766.72 cm-1. The anticandidal activity of nhhE of S. costus roots was confirmed from the results, and the treated cotton fabrics with nhhE of S. costus possessed observable activity against C. albicans. Data could recommend the practical usage of S. costus extracts, particularly nhhE, as influential natural bioactive sources for combating pathogenic Candida spp.

Comparison between the Antioxidant and Antidiabetic Activity of Fenugreek and Buckthorn in Streptozotocin-Induced Diabetic Male Rats.

This study is aimed at comparing the antidiabetic and antioxidant potential of fenugreek and buckthorn which are commonly used in modulating diabetes in the Middle East. In this study, the antioxidant and antidiabetic activity of the aqueous extracts of the leaf and seed of fenugreek and buckthorn was tested in streptozotocin-induced diabetic male rats fed with a fat-rich diet for 8 weeks. Thirty-six male albino rats were divided into 6 groups (n = 6); the 1st group was the negative control. Diabetes was induced in the other 30 rats using streptozotocin, which were then divided into 5 groups; the 2nd was the untreated positive diabetic group, the 3rd was treated with fenugreek leaf aqueous extract, the 4th was treated with the fenugreek seed aqueous extract, the 5th was treated with buckthorn leaf aqueous extract, and the 6th was treated with buckthorn seed aqueous extract. The positive control group showed an increase in blood sugar, glycated hemoglobin, liver function enzymes, lactate dehydrogenase, kidney indices, total cholesterol, triglycerides, low- and very-low-density lipoprotein, immunoglobulins, and lipid peroxidation and a decrease in high-density lipoprotein, albumin, and antioxidant activity. The histology of the liver and testes showed severe histopathological alterations. Rats of groups 4-6 that were treated with the aqueous extract of the leaf and seed extract of fenugreek and buckthorn showed improvement of all biochemical and histopathological parameters. The seed extract of fenugreek and buckthorn showed more antioxidant activity than their leaves.